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We
are able to model the photoisomerization process in molecules like
stilbene (above) and azobenzene. These molecule exist in two stable
conformations: trans
(top left) and cis
(bottom left), and are converted from one configuration to the other
when they are excited optically (middle panel). In our simulations,
we perform ensembles to describe isomerization mechanism, time, and
quantum yield (right panel). The photo switchable molecules have
potential applications ranging from optical storage devices,
photo-orientation of liquid crystals, control of peptide
conformations, and control of CO2
adsorption in porous metal organic frameworks.

This
work was supported by the Office of Science, Basic Energy Sciences
in the US Department of Energy (Grant
No.DE-SC0006527 ).

We explore the effect of crystallographic strain on the electronic configuration of materials such as CuGaO2 using high-throughput calculations. We can see how the crystal structure responds to iron substitution at the gallium sites and observe how the electronic transitions change as a result. We use very high-throughput calculations and data-mining techniques to determine the preferred crystal positions of the iron atoms relative to each other. We find that at a certain impurity level the disorder in the material becomes global, unlocking previously forbidden optoelectronic transitions throughout the material.

This work is supported by the National Science Foundation through NSF DMR 09-03225 and a subcontract from NETL (URS RES) for Work Activity 0004000.6.600.007.002.420.000.005 ARRA ICMI Project, Element 420, Photo Active Materials.

We combine
computational and experimental effort together to explore the
interaction between biomolecules and gold nanoparticles. Starting
with small amino acid molecule, we have investigated the anchoring
pattern for cysteine zwitterion attached on gold nanoparticle. Our
results support the attaching mode recognized in solid state NMR
studies, which indicate a double layer of L-cysteine molecules is the
likely configuration.

We have expanded our
studies to small peptide molecules with cysteine as terminated
component. What we are curious herein is if the interaction will be
different once cysteine presented as part of peptide. These
computational results may be applicable to gain a better
understanding of how peptides interact with gold nanoparticles.

This work is supported by Grant
PRF51290-ND6 from the American Chemical Society Petroleum Research
Fund.

We predict possible material's that catalyze the photo-degradation of organic chemical pollutants using our high-throughput computational techniques. The removal of such chemicals from waste water in industrial processes' is a serious issue in many industries. For example, we study a material that helps break down methylene blue in waste water by replacing indium sites in NaInO2 with iron.

Jonathan W. Lekse, Barry Haycock, James P. Lewis, and Christopher Matranga. 2013. "The Effect of Electronic Structure Changes in NaInO2 and NaIn0.9Fe0.1O2 on the Photoreduction of Methylene Blue" In preparation.

This work is supported by the National Science Foundation through NETL (URS RES) for Work Activity 0004000.6.600.007.002.420.000.005 ARRA ICMI Project, Element 420, Photo Active Materials.